TEHRAN, Iran — The U.N. chief got little satisfaction Sunday at the close of his trip to Tehran, snubbed by Iran’s leader over international demands to stop enriching uranium and ignored in warnings not to incite hatred by questioning the Holocaust.

In a provocative move on the final day of Kofi Annan’s two-day visit, Iran announced it would host a conference to examine what it called exaggerations about the Holocaust, during which more than 6 million Jews were killed by the Nazis.

The move was sure to draw new international condemnation of Iran’s stance on Jews. Hours after the announcement, Annan repeated his displeasure over an exhibition in Tehran of cartoons mocking the Holocaust that was opened as a response to Western caricatures of Prophet Muhammad.

“I think the tragedy of the Holocaust is an undeniable historical fact and we should really accept that fact and teach people what happened in World War II and ensure it is never repeated,” Annan told reporters.

He commented after a meeting with President Mahmoud Ahmadinejad, but the hard-line Iranian leader didn’t accompany the U.N. chief to the news conference.

Ahmadinejad has drawn strong condemnations around the globe for calling the Nazis’ slaughter of Jews a myth and saying Israel should be wiped off the map or moved to Germany or the United States.

The Holocaust exhibit is being held to underline outrage over Prophet Muhammad caricatures in Western media. Islam forbids picturing Muhammad at all, but Muslims also were angered by the cartoons’ negative tone, such as one showing the prophet wearing a turban shaped as a bomb with a burning fuse.

Annan first raised his concerns about the exhibit during a meeting Saturday with Iranian Foreign Minister Manoucher Mottaki, according to the U.N. chief’s spokesman, Ahmad Fawzi. He quoted Annan as saying that “we should avoid anything that incites hatred.”

No suspension before negotiationsAnnan’s visit came after Iran ignored the U.N. Security Council’s Thursday deadline for Tehran to halt uranium enrichment, opening the door to possible sanctions over concerns that the Iranians are trying to develop atomic weapons.

“On the nuclear issue, the president reaffirmed to me Iran’s preparedness and determination to negotiate” a solution to the nuclear confrontation, Annan said at the news conference.

However, Ahmadinejad “reiterated that he did not accept suspension before negotiations,” the U.N. chief said, conveying Iran’s rejection of a condition set by the five permanent members of the Security Council plus Germany.

In June, the six nations offered Iran a package of economic and diplomatic incentives to limit its nuclear program. Iran didn’t respond until Aug. 22, rejecting the condition that it stop enriching uranium before talks. The content of its response has not been made public.

Tehran hid its nuclear program for 18 years and its continued lack of full cooperation with U.N. inspectors has increased suspicions about Iranian aims. The oil-rich nation insists the program is peaceful, intended only to produce fuel for nuclear reactors that generate electricity.

Iran’s slowness in responding to the incentives package prompted the Security Council to issue a resolution July 31 ordering it to halt uranium enrichment by the end of August.

On Sunday, Mottaki said the council issued the resolution “under pressure from the United States and Britain” and described it as a “mistake” and a “black mark against them.”

State television quoted Ahmadinejad as saying he was ready to negotiate, but the onus was on Western countries to repair relations with Tehran.

“Iran’s trust has been undermined during the past three years,” he said. “They (the West) should try to win our trust to solve the issue.”

Although Iran’s defiance of the U.N. deadline opens the way for the Security Council to consider sanctions, it is unlikely punitive measures will come soon. Both Russia and China, which are among the council’s veto-holding permanent members, oppose strong sanctions.

The European Union is taking another shot at diplomacy this week, with EU foreign policy chief Javier Solana planning to meet with Iran’s chief nuclear negotiator, Ali Larijani. But the bloc said Saturday that it would not give much time for the effort to produce results.

Support for Lebanon resolutionAnnan got a more favorable response from Iranian leaders on Lebanon, where Tehran is a backer of the Hezbollah guerrilla group and is believed by many to be its top arms supplier.

Ahmadinejad “reaffirmed his country’s support for the implementation of resolution 1701,” Annan said of the U.N. resolution that ended the 34-day war between Israel and Hezbollah and calls for preventing the rearming of the Shiite militants in Hezbollah.

But Annan did not disclose the specifics of his talks on Lebanon. Mottaki, after meeting with Annan on Saturday, made a vague promise to support the resolution, but did not directly mention Hezbollah.

Annan said Friday that Syria, another key Hezbollah ally, promised to patrol its side of the frontier to prevent arms deliveries, though Israel was skeptical that would happen.

Still, the Syria stopover has been Annan’s most upbeat on his tour of the Middle East to promote peace.

He had little success in Beirut, where Prime Minister Fuad Saniora said Lebanon would be the last Arab country to make peace with Israel. In Jerusalem, Israeli Prime Minister Ehud Olmert rebuffed Annan’s call for quickly lifting its air and sea blockade of Lebanon.